Can you get CRTs with VGA input? Would that be preferable to an HDTV with VGA?
They do exist, I remember though out my elementary to high school years they were using them with G3 or G4 computers and calling them "COWS" or Computer On WheelS. I really do wish I could have wrote down some model numbers since these TV's had it all, many component inputs that could accept 240p, VGA, a few even had SCART which was very uncommon for American TV's.
Ask for this situation you could go the VGA to HDMI route. The Atlona upscaler you linked seems to work according to someone in the ratings reviews. The only thing is to get audio on the HDMI connection your VGA cable or box needs to have audio out than can be plugged into the input 3.5mm jack on the upscaler.
If your cable has RCA (white and red) connectors for audio there's an adapter for that as well to convert it to 3.5mm.
http://www.amazon.com/Female-3-5mm-Stereo-Male-inch/dp/B000I23TTO